NCT07363720 · Takeda
A Trial of TAK-861 for the Treatment of Narcolepsy With Cataplexy
What this study is about
The main aim of this study is to assess how effective TAK-861 is for treating narcolepsy type 1 and if this effect is maintained over time.
View original scientific description
The main aim of this study is to assess how effective TAK-861 is for treating narcolepsy type 1 and if this effect is maintained over time. Participants will take TAK-861 for a few months and if they meet certain criteria, they will be randomly assigned (by chance, like flipping a coin) to continue taking TAK-861 or take placebo (fake medicine) for up to 4 weeks to see if their narcolepsy symptoms return.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- The participant has a body mass index (BMI) within the range 18 to 40 kilograms per square meter (kg/m\^2).
- The participant has an International Classification of Sleep Disorders, Third Edition (ICSD-3) or International Classification of Sleep Disorders, Third Edition, Text Revision (ICSD-3-TR) diagnosis of NT1.
- The participant is positive for the human leukocyte antigen (HLA) genotype Major Histocompatibility Complex, Class II, DQ Beta 1 (HLA-DQB1\*06:02) or results from radioimmunoassay indicate the participant's CSF OX/hypocretin-1 concentration is ≤110 pg/mL (or less than one-third of the mean values obtained in normal participants within the same standardized assay).
Exclusion criteria
- The participant has a current medical disorder, other than narcolepsy with cataplexy, associated with EDS.
- The participant a) has a history of myocardial infarction, b) has a history of clinically significant hepatic disease, thyroid disease, coronary artery disease, cardiac rhythm abnormality or heart failure, or c) has any medical condition (such as unstable cardiovascular, pulmonary, renal or gastrointestinal disease.
- The participant has current or recent (within 6 months) gastrointestinal disease that is expected to influence the absorption of drugs.
- The participant has a history of cancer in the past 5 years.
- The participant has a clinically significant history of head injury or head trauma.
- The participant has a history of epilepsy, seizure, or convulsion (except for a single febrile seizure in childhood).
- The participant has a history of cerebral ischemia, transient ischemic attack (less than 5 years from screening), intracranial aneurysm, or arteriovenous malformation.
Where
- Redwood City, California
- Brandon, Florida
- Miami, Florida
- Southfield, Michigan
- Middletown, New Jersey
- Durham, North Carolina
- Winston-Salem, North Carolina
- Cincinnati, Ohio
- Cleveland, Ohio
- Columbia, South Carolina
- Austin, Texas
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 8, 2026 · Source of record for eligibility and locations